The blanket of snow covering much of Britain is finally giving way to a rapid thaw, bringing the risk of flooding for parts of the country, forecasters said.
The latest heavy snow storms on Friday night into Saturday left hundreds of people stranded overnight as drivers on motorways in the north of England were forced to abandon their cars.
The M6 was blocked in both directions between junctions 25 and 27 in Lancashire when a sudden burst of more than a foot of snow brought drivers to a standstill, the Highways Agency said.
Many became stuck along the stretch of motorway between Wigan and Standish after struggling to make it up inclines in the treacherous conditions, while a number of accidents including jack-knifed lorries also blocked lanes.
Weather experts have now warned that milder temperatures tonight will cause snow to thaw rapidly, with heavy rain expected to bring further flooding problems.
The Environment Agency (EA) has six flood warnings in place for south-west England, the second highest alert which means flooding is expected.
More than 100 flood alerts, meaning flooding is possible, were also in place across the country after the agency warned of an increased risk of surface water and river flooding.
Mountain rescue workers were drafted in overnight to help with rescue operations and check on the condition of drivers stranded by the snow.
A diabetic man was taken to Royal Blackburn Hospital after falling ill, while an ambulance taking a female patient to Royal Preston Hospital had to be dug out of the snow by Bowland Pennine Mountain Rescue team.
Phil O’Brien, team leader of Bowland Pennine Mountain Rescue, said: “It was potentially a very serious situation. The Highways Agency managed to get people moving at about 4.30 to 5am.
“There were hundreds of cars stuck but most people seemed in good spirits.”
Some of the stranded drivers passed the time having snowball fights and building snowmen, while others abandoned their cars completely.
Conservative MP for Morecambe and Lunesdale David Morris, who was stuck on the south-bound carriageway, said: “We’ve ground to a halt on both sides. Nothing is really moving.
“But the emergency services have been fantastic and are doing the best for us, and everyone is in good spirits.
“I’ve just seen a snowball fight and the man next door to me has built a snowman on top of his car roof - it’s very surreal.”
Prime Minister David Cameron took to Twitter today to express his sympathy for those caught up in the snow.
He tweeted: “Huge sympathy for those affected by heavy #uksnow. Govt working closely with transport operators to minimise impact on everyone.”
Heavy rain combined with rapidly melting snow could cause further disruption on roads, as well as flooding to properties, the EA said.
Communities in Wales, the south west of England, the Midlands and the north of England were being urged to prepare for possible flooding.
Around 18 buildings flooded in various locations across Wales last night, including two houses in Solva, Pembrokeshire and two in Dolgellau, North Wales.
An EA spokesman said: “Emergency teams from the Environment Agency will be out in force throughout the weekend shoring up defences, monitoring river levels and clearing blockages from watercourses.
“Those in areas at risk should check the Environment Agency website for the latest information - www.environment-agency.gov.uk/flood - and sign up for free flood warnings on the Environment Agency’s website or by calling the Environment Agency Flood Line on 0845 988 1188.”
Paul Knightly, a forecaster for MeteoGroup, the weather division of the Press Association, said two thirds of the country was covered in snow, which was likely to begin melting tonight.
Temperatures were expected to remain around 3C or 4C today before rising to up to 10C in the south tomorrow, with wet and windy weather forecast.
Mr Knightley said: “The rapid thaw will commence overnight and we’ll see river levels start going up pretty rapidly, bringing the risk of localised flooding.”
Staffordshire County Council pledged that snowploughing crews and gritters would be out to help keep roads clear after between two and four inches of snow fell in the area overnight.
Snow grounded planes at Leeds Bradford Airport but it has now re-opened.
A family had to be evacuated when the gable end of their house collapsed, apparently under the weight of fresh snow in Barnsley, South Yorkshire.
Meanwhile, hundreds of swimmers braved the freezing weather today to take part in the UK Cold Water Championships at Tooting Bec Lido, south London.
The death toll during the recent cold snap, which is in double figures, is thought to have risen further as it was feared a man in his 30s or 40s might have frozen to death after going missing in woodland.
His body was found on Thursday night after four friends went to Newmarket police station in Suffolk reporting that he had not been seen for four days. The men had been searching for him and found him dead in a wooded area.
The death is being treated as unexplained but one theory is he died in the freezing temperatures.
A father died on Thursday when his car skidded into a river just before his wife’s vehicle also plunged into the icy water.
BBC employee David Cox, 42, was taking his 11-year-old daughter Tess to school when their Toyota Aygo left the path and crashed into the River Wye in Derbyshire.
Moments behind them in a separate car, a Toyota Rav 4, was his wife Ruth, 39, and son Ioan, nine.
Mrs Cox also lost control as she drove along the bridlepath near the Monsal Trail, north of the A6.
The children and their mother managed to get out of the cars and safely to shore but Mr Cox was unable to escape.
Neighbours tried to save him but it is believed he was trapped for around 40 minutes. He died in hospital.
Other casualties of the cold spell include postman John Bircham, 57, who collapsed soon after he was towed out of a snowdrift in Dulverton, Somerset, last Saturday, and Bernadette Lee, 25, who was found collapsed in the snow in Deal, Kent, on Sunday following a night out.